Re: [alsa-devel] [PATCH 2/2] ASoC: atmel-pcm: use generic dmaengineframework

From: Bo Shen
Date: Tue Jul 02 2013 - 21:34:30 EST


Hi Lars-Peter,

On 7/2/2013 23:34, Lars-Peter Clausen wrote:
On 07/02/2013 11:04 AM, Bo Shen wrote:
[...]
-/*--------------------------------------------------------------------------*\
- * DMAENGINE operations
-\*--------------------------------------------------------------------------*/
-static bool filter(struct dma_chan *chan, void *slave)
-{
- struct at_dma_slave *sl = slave;
-
- if (sl->dma_dev == chan->device->dev) {
- chan->private = sl;
- return true;
- } else {
- return false;
- }
-}

I'm wondering why is filtering no longer required?

Now this is handled by at_dma_filter in at_hdmac driver. More information, you can reference: <driver/dma/at_hdmac.c> file

[...]
+ slave_config->dst_addr = (dma_addr_t)ssc->phybase + SSC_THR;
[...]
+ slave_config->src_addr = (dma_addr_t)ssc->phybase + SSC_RHR;

Change the type of phybase to dma_addr_t

It should be:
slave_config->dst_addr = (dma_addr_t)(ssc->phybase + SSC_THR);
slave_config->src_addr = (dma_addr_t)(ssc->phybase + SSC_RHR);

[...]
}

-static int atmel_pcm_dma_prepare(struct snd_pcm_substream *substream)
-{
- struct snd_soc_pcm_runtime *rtd = substream->private_data;
- struct atmel_pcm_dma_params *prtd;
-
- prtd = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
-
- ssc_writex(prtd->ssc->regs, SSC_IER, prtd->mask->ssc_error);
- ssc_writex(prtd->ssc->regs, SSC_CR, prtd->mask->ssc_enable);

These writes are also completely lost

This will be moved to DAI driver startup callback function.

-
- return 0;
-}

I think it would also be good to get rid of any references to the ssc struct
from the DMA driver and move them over to the DAI driver.

I will try to implement this in next version patch.

Thanks.

- Lars


Best Regards,
Bo Shen

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